Many different types of user interface devices and methods are currently available. Common tactile interface devices include a computer keyboard, a mouse and a joystick. Touch screens detect the presence and location of a touch by a finger or other object within the display area. Infrared remote controls are widely used, and “wearable” hardware devices have been developed, as well, for purposes of remote control.
Computer interfaces based on three-dimensional (3D) sensing of parts of a user's body have also been proposed. For example, PCT International Publication WO 03/071410, whose disclosure is incorporated herein by reference, describes a gesture recognition system using depth-perceptive sensors. A 3D sensor, typically positioned in a room in proximity to the user, provides position information, which is used to identify gestures created by a body part of interest. The gestures are recognized based on the shape of the body part and its position and orientation over an interval. The gesture is classified for determining an input into a related electronic device.
Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that to the extent any terms are defined in these incorporated documents in a manner that conflicts with the definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered.
As another example, U.S. Pat. No. 7,348,963, whose disclosure is incorporated herein by reference, describes an interactive video display system, in which a display screen displays a visual image, and a camera captures 3D information regarding an object in an interactive area located in front of the display screen. A computer system directs the display screen to change the visual image in response to changes in the object.
Three-dimensional human interface systems may identify not only the user's hands, but also other parts of the body, including the head, torso and limbs. For example, U.S. Patent Application Publication 2010/0034457, whose disclosure is incorporated herein by reference, describes a method for modeling humanoid forms from depth maps. The depth map is segmented so as to find a contour of the body. The contour is processed in order to identify a torso and one or more limbs of the subject. An input is generated to control an application program running on a computer by analyzing a disposition of at least one of the identified limbs in the depth map.
Some user interface systems track the direction of the user's gaze. For example, U.S. Pat. No. 7,762,665, whose disclosure is incorporated herein by reference, describes a method of modulating operation of a device, comprising: providing an attentive user interface for obtaining information about an attentive state of a user; and modulating operation of a device on the basis of the obtained information, wherein the operation that is modulated is initiated by the device. Preferably, the information about the user's attentive state is eye contact of the user with the device that is sensed by the attentive user interface.